Island



3 Sheets-Sheet 1.

J. LUTHER.

Coffee Mill;

Patented Aug. "H, 1843.

' i V 7 3 sheets-sheets.

J. LUTHER.- 1

, Coffee m.

Patented Aug. 11,1843. 1

PATENT OFFICE.

JOHN LUTHER, OF WARREN, RHODE "ISLAND.

COFFEE-MILL.

Specification of Letters Patent No. 3,215, dated August 11, 1843.

To all whom it may concern:

Be it known that I, JOHN LUTHER, of Varren, in the county of Bristol, in the\ State of Rhode Island, have invented a new and Improved Mode of Constructing Coffee or Spice Mills; and I do hereby declare that the following is a full and exact description.

The nature of my invention consists in constructing the mill of a flat shape with an aperture at the top in the edge of the shell of the mill where the hopper is inserted, by which the grains to be ground whenput into the hopper fall directly upon the top of the wheel, and the chambero, into which the grains pass from the hopper is extended below and around the shaft so that the whole space measured by the surface ofthe wheel may be filled with the grains which may be ground at the same time. I also use a gate in the hopper of the mill which is raised and lowered by means of a screw by which the feeding of the mill is regulated. In consequence of the flat shape of the mill the grooves of the two parts of the mill do not come in contact and wear upon each other. Thus the mill which I construct by the improvement which I have made will grind much faster and last much longer than any other mill.

I construct my mill in the following manner, viz: I construct a circular flat plate or shell of cast iron with a rim around its edge or circumference, grooved on its inner surface represented by figure 1 in the drawing annexed hereto. This shell has an aperture or chamber at the top into which the grain is received to be ground which is marked a in Fig. 1 and an aperture marked 1) in the drawing at which the grain passes out after it is ground. In the center of this shell is a hole for the shaft of the wheel hereafter described. I then construct acast iron wheel of dimensions which will permit it to revolve within the rim of the plate or shell above described having grooves on one surface represented by Fig. 2 in the drawing. This shell has a shaft marked 0 in Fig. 2 projecting from its center, and teeth raised upon its circumference marked i i in Fig. 2.

I then construct a back board represented by Fig. 3 in the drawing with a gate hung upon alt so as to raise and fall in the hopper marked 9 in Fig. 3 and having placed the wheel Fig. 2 within the rim of the shell or plate Fig. l, with its shaft 0 passing through the hole in the center of the shell'Fig. 1.

I attach the shell or plate Fig. l to this back board by means of screws at'the points cl, (Z, which pass through the board and are held by nuts on the end of the screws. I then construct a hopper represented by Fig. 4 in the drawing, the narrow extremity of which is introduced into the aperture or chamber a in the plate shell Fig. 1, and which is attached by small nails to the back board above the shell Fig. 1. In this hopper the gate g is hung upon the back board upon wire hinges upon its upper edge, which is raised and lowered so as to fill up more or less space in the hopper by means of screw which passes through the back board and presses against the gate raising or lowering it by turning the screw behind the mill. I have another screw which passes through the back board and presses against the wheel which by being turned one way or the other increases or diminishes the space between the wheel and the shell of the mill.

Having thus completed the mill I attach a crank to the end of the shaft which passes I through the hole in the center of the plate or shell Fig. 1, by which the wheel is turned and the grain is ground, by the power applied at the end of the crank. Fig. 5 represents the mill thus constructed.

What I claim as my invention, and desire to secure by Letters Patent is The extending the chamber a, into which the grains pass from the hopper, below and around the shaft, whereby the grain is presented to a greater grinding surface as described.

JOHN LUTHER.

, Signed in presence of- ALFRED BowvoR'rH,

AMASA L. WnsTooTr. 

